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61.
Chromosomal mapping and nucleotide sequence of a human DNA autonomously replicating sequence 总被引:1,自引:0,他引:1
A 1.1-kb human DNA fragment (ARSH1) capable of functioning as a putative origin of replication in yeast cells has been characterized both by in situ hybridization to human metaphase chromosomes and by DNA sequencing. Our hybridization studies show a preferential localization of ARSH1 in chromosome regions 1p34-36 and 2q34-37. DNA sequence analysis indicates that in addition to the consensus sequence required for ARS function in yeast cells, nuclear matrix-associated DNA motifs are also present in the 1.1-kb fragment. These results suggest that ARSH1 sequences may serve as points of anchorage to the nuclear matrix for chromosomes 1 and 2. 相似文献
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Tahsin Gulzar Nizam Uddin Bina Shaheen Siddiqui Syed N.H. Naqvi Sabira Begum Rajput Muhammed Tariq 《Phytochemistry letters》2013,6(2):219-223
Six bioactive compounds were isolated from the seeds extract of Piper nigrum Linn. following a larvicidal activity guided isolation against 4th instar larvae of Aedes aegypti L., a Dengue vector mosquito and a carrier of yellow fever. Their structures were elucidated using spectroscopic methods including HR-EI-MS, FAB-MS, 1H and 13C NMR (Broad Bond Decoupled, & DEPT), and 2D-NMR techniques (1H–1H COSY, NOESY, HMQC, HMBC, & 2D-J-resolved). These include three new constituents namely pipilyasine (1), pipzubedine (2) and pipyaqubine (3), and three known constituents pellitorine (4), pipericine (5) and piperine (6). The larvicidal activity was determined by WHO method. 相似文献
64.
A field experiment was conducted to determine the seasonal patterns of arbuscular mycorrhiza (AM) in a dryland winter wheat
(Triticum aestivum L.) system and to determine wheat growth and P uptake responses to inoculation with mycorrhizal fungus. Broadcast-incorporated
treatments included (1) no inoculation with mycorrhizal fungus, with and without P fertilizer, and (2) mycorrhizal fungal
inoculation at a rate of 5000 spores of Glomus intraradices (Schenck and Smith), per 30 cm in each row, with and without fertilizer P. Winter wheat was seeded within a day after treatments
were imposed, and roots were sampled at five growth stages to quantify AM. Shoot samples were also taken for determination
of dry matter, grain yield and yield components, and N and P uptake. No AM infection was evident during the fall months following
seeding, which was characterized by low soil temperature, while during the spring, the AM increased gradually. Increases in
wheat grain yields by enhanced AM were of similar magnitude to the response obtained from P fertilization. However, responses
differed at intermediate growth stages. At the tillering stage, P uptake was mainly increased by P fertilization but not by
fungal inoculation. At harvest, enhanced AM increased P uptake regardless of whether or not fertilizer P was added. The AM
symbiosis increased with rising soil temperatures in the spring, in time to enhance late-season P accumulation and grain production.
Accepted: 15 July 1998 相似文献
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Naderi Gharehgheshlagh Soheila Fatemi Mohammad Javad Jamili Shahla Nourani Mohammad Reza Sharifi Ali Mohammad Saberi Mohsen Amini Naser Ganji Fatemeh 《International journal of peptide research and therapeutics》2021,27(1):317-328
International Journal of Peptide Research and Therapeutics - Natural compounds extracted from marine organisms consisting of biological active materials like collagen provide a major source of... 相似文献
67.
Najafzadeh Mohammad Javad Dolatabadi Somayeh de Hoog Sybren Esfahani Mahmoud Karimizadeh Haghani Iman Aghili Seyed Reza Ghazvini Roshanak Daei Rezaei-Matehkolaei Ali Abastabar Mahdi Al-Hatmi Abdullah M. S. 《Mycopathologia》2020,185(3):515-525
Mycopathologia - Fungi of the genus Fusarium are well known as major plant pathogens but also cause a broad spectrum of human infections. Sixty-three clinical isolates, collected during... 相似文献
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Lin Yu-Jia Roa-Ureta Ruben H. Basali Abdullajid Usama Alcaria Joselito Francis Albaran Lindo Reynaldo Qurban Mohammad A. Prihartato Perdana K. Qasem Ali Rabaoui Lotfi 《Coral reefs (Online)》2021,40(6):1741-1756
Coral Reefs - The Arabian Gulf is a natural laboratory to examine how subtropical coral reef ecosystems might change in responding to recurring heating events because of uniquely high water... 相似文献